When to plant Calendula in Osage County, MO
Aim to plant Calendula in Osage County on or after March 9; the window stays open through March 30. Osage County's 207-day frost-free season gives you enough for a full main crop and a short fall succession.
When to Plant Calendula in Osage County, MO
Top priorities for Osage County, Missouri gardeners in July
July is a pivotal month for Osage County, Missouri gardens. Focus on these tasks first and you'll set up the rest of the season for success.
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Start harvesting calendula
If you can't use it all right away, check the food-preservation section of your planner.
To set up a strong August, finish these tasks
- First harvests: calendula
Calendula (Calendula officinalis) is a cheerful, edible-flowered cool-season annual valued by herbalists, chefs, and gardeners alike. Its golden-orange petals are used in salves, teas, and as a saffron substitute. Hardy enough to tolerate light frosts, it blooms prolifically in spring and fall, taking a pause during the hottest weeks of summer.
Osage County, Missouri is in USDA Zone 6b. The average last spring frost is April 6 and the first fall frost is October 30, giving you a growing season of approximately 207 days.
At an elevation of 1,300 feet, Osage County receives approximately 38.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 90°F, providing good warmth for Calendula during the growing season.
Osage County Soil Profile
Soil Type
Silt Loam
Soil pH
5.5-6.7
Drainage
Well Drained
Calendula Planting Risk Windows
Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.
Soil Compatibility in Osage County
How your county's soil matches Calendula's growing requirements.
Soil pH
Your soil pH (5.5–6.7) is within Calendula's preferred range (5.5–7.0).
Soil Texture
The silt loam soil in Osage County is excellent for Calendula — good drainage, moisture retention, and nutrient holding capacity.
Organic Matter
Organic matter is moderate (2.4%). Annual compost additions will help Calendula.
How to Plant Calendula
Succession Planting Calendula
Sow every 5.7 weeks. Last sowing by Aug 21 to harvest before frost.
Calendula Water Budget
Monthly Watering Guide for Calendula
Calendula needs approximately 0.5 inches of water per week (2.2" per month). Here's how your county's rainfall compares month by month.
| Month | Calendula Needs | Rainfall | You Supplement | Action |
|---|---|---|---|---|
| Jan | — | 1.6" | 0" | ❄️ Dormant |
| Feb | — | 1.8" | 0" | ❄️ Dormant |
| Mar | — | 2.5" | 0" | ❄️ Dormant |
| Apr | 2.2" | 3.8" | 0" | ✅ Rainfall sufficient |
| May | 2.2" | 5.2" | 0" | ✅ Rainfall sufficient |
| Jun | 2.2" | 4.8" | 0" | ✅ Rainfall sufficient |
| Jul | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Aug | 2.2" | 3.9" | 0" | ✅ Rainfall sufficient |
| Sep | 2.2" | 3.6" | 0" | ✅ Rainfall sufficient |
| Oct | 2.2" | 2.8" | 0" | ✅ Rainfall sufficient |
| Nov | — | 2.4" | 0" | ❄️ Dormant |
| Dec | — | 2.3" | 0" | ❄️ Dormant |
Water needs are for active growing months only (Apr–Oct in Osage County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.
Calendula Heat Requirements (GDD)
What are Growing Degree Days (GDD)?
Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.
Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.
Calendula Planting Timeline — Osage County, MO
Calendula Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Start Indoors | February 23 | Feb 23 – Mar 9 |
| Transplant Outdoors | April 6 | Apr 6 – Apr 20 |
| Direct Sow | March 9 | Mar 9 – Mar 30 |
| Bloom | May 25 | May 25 – Aug 31 |
Plant 0.3" deep · 9" apart · Rows 12" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | Start Indoors |
| March | Start Indoors Direct Sow |
| April | Transplant Outdoors |
| May | Bloom |
| June | Bloom |
| July | Bloom |
| August | Bloom |
| September | — |
| October | — |
| November | — |
| December | — |
Growing Conditions
☀️ Sun
Full Sun (6-8+ hours)
💧 Water
0.5"/week · Natural rainfall sufficient
📅 Days to Maturity
50–70 days
🧪 Soil pH
Needs 5.5–7 · Your soil: ideal
🗺️ USDA Zone
Zone 6b
📆 Growing Season
207 days in Osage County
Growing Tips for Calendula in Osage County
Direct sow Calendula outdoors after April 06 in Osage County when soil has warmed and frost danger has passed.
Common pests for Calendula in this region include aphids and slugs. Use row covers early in the season and inspect plants weekly.
General growing tips
Direct-sow in early spring as soon as soil can be worked — seeds germinate in cool soil (50-65°F). In zones 7+, also sow in fall for winter/spring bloom. Deadhead consistently to extend bloom. Plants self-seed readily; save a few spent heads and allow them to drop. Harvest petals when flowers are fully open for best flavor and medicinal value.
Companion Planting
Good Companions
Check more plant combinations with our Companion Planting Checker →
Calendula in Other Locations
Frequently Asked Questions
When should I plant Calendula in Osage County, MO?
Osage County is in Zone 6b with an average last frost of April 6. Plan your Calendula planting based on this frost date — see the calendar above for exact timing.
What planting zone is Osage County, MO?
Osage County, Missouri is in USDA Hardiness Zone 6b. The average last spring frost is April 6 and first fall frost is October 30.
When should I plant Calendula in Osage County, MO?
In Osage County, MO, plant Calendula after the last frost (around April 6) and before the first frost (around October 30). Best results when soil holds above 50°F.
What growing zone is Osage County, MO for Calendula?
Osage County sits in USDA Zone 6b. Calendula grows reliably in zones 2a through 11b, so it's a good fit here.
Can Calendula grow in Osage County's climate?
Yes — Calendula grows well in Osage County's temperate climate. Osage County averages a 207-day frost-free season, with last frost around April 6 and first frost around October 30.
Your Osage County Garden Planner — Free
A 22-page printable planner built for Osage County (Zone 6b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.